/**
 * Test.java created by zhangzhidong 
 * at 下午5:03:55 2017年9月9日
 */
package jdk.jdk18;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.LinkedList;

import jdk.effectivejava.ExtendsTest;

/**
 * @author zhangzhidong<br>
 * comment generated at 2017年9月9日下午5:03:55<br>
 * 
 */
class A{
	A(){
		System.out.println("a");
	}
	A(int x){
		
	}
	
}
class B extends A{}

public class Test {
	public static void main(String[] args) {
		String [] s=  new String[]{"abc","def","xyz","jqk",null};
		Arrays.sort(s,(x,y)->x==null?-1:(y==null?1:x.compareTo(y)));
		System.out.println(Arrays.toString(s));
		LinkedList<A> obj1 = new LinkedList<>();
		LinkedList<? extends A> obj2 = obj1;
		ArrayList<Class<? extends A>> l = new ArrayList<>();
		l.add(A.class);
		l.add(B.class);
		
	}
}
